Microsoft Word sim800c-ds application Note V

Version History 

 

Date 

Version 

Description of change 

Author 

2015-7-30 

1.00 

Original 

Yong.lu 

 

 

 

Scope 

This document describes what SIM800C-DS is and how to start with SIM800C-DS: the totally 

new module which supports Dual SIM Dual Standby function. 

 

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                                                                                                                Smart Machine Smart Decision                                       

SIM800-DS_Application Note_V1.00                                                                                             2015-07-30 

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1.  Introduction 

SIM800C-DS supports Dual SIM Dual Standby function. There is only one modem (one BB/one 

RF) managing two SIM cards at the same time. 

 

The network behaviors of the two SIM cards are totally independent. The Idle Services on both 

SIM cards are in parallel (paging reception, reselection...) which means that the two SIM cards 

can register to different network operators. And cell selection/cell reselection/paging monitoring 

can be observed on the two SIM cards. 

 

Also module is able to do CS/PS calls on any of the two SIM cards. But only one connection 

(CS/PS) at a time AND no activity on other SIM is possible (either idle or not connected). 

 

The main difference between SIM800C and SIM800C-DS: 

1)  Protocol stack is duplicated on SIM800C-DS. 

2)  New module creation for hardware SIM swap management on SIM800C-DS: DSCV. 

3)  New AT commands to change default SIM card: AT+CDSDS. 

4)  New AT commands to write IMEI for the second SIM card: AT+SIMEIDS. 

5)  Some URC on the SIM card inserted to the second slot are appended with “DS” to indicate 

TE that this URC is from the second SIM card. 

 

 

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                                                                                                                Smart Machine Smart Decision                                       

SIM800-DS_Application Note_V1.00                                                                                             2015-07-30 

7